I've code to get the sequence number like this: vals['sale_number'] = self.pool.get('ir.sequence').get(cr, uid, 'nadine.sale')

the sequence number succesly generate but when I see the sequence table the value next number still 1 (it must be 2) well it does'nt have problem when I want to get the next number again using above code , I get number 2. It get problem when in my developement I got technicall error about my code, then when I want to get the sequence number again the sequence number is back to 1.

So how I solve this?